The aim of this predoctoral training program in Chemistry and Chemical Biology (CCB) is to foster research exploits and develops chemical strategies to understand and control fundamental biological processes. The program is distinctive in its orientation toward the study of molecules in living systems from a chemical perspective. The program provides a rich venue for chemical research as it interfaces with biology by bringing together 47 investigators and resources from seven departments primarily at UCSF and also at UCB. The research has direct relevance to national priorities in human health and addresses central problems in chemical biology including, molecular recognition, protein folding, signal transduction, protein trafficking, computer aided design, combinatorial synthesis, genomics, proteomics, systems biology and quantitative approaches to cellular signaling. These studies use systems, ranging from bacteria to humans and encompass technologies including chemical synthesis, crystallography, NMR spectroscopy, mass spectrometry and computational modeling. Approximately 9 students are enrolled from about 100 applicants after a rigorous application process that culminates in personal interviews. At final size we expect 12 outstanding students per year. Underrepresented minority candidates are actively sought in an extensive series of programs including the Science Education Partnership and an undergraduate Summer Research Training Program. The aim of the program is accomplished through: 1) a combination of carefully designed didactic courses;2) a lab rotation system that provides three meaningful research experiences in distinctly different labs each of which culminates in an oral presentation and a written evaluation of the trainee's performance from the faculty preceptor;3) oral presentations and defense of scientific information and hypotheses via tutorial training with faculty in a journal club setting;4) an intensive oral and written qualifying exam experience;5) the student's individual thesis research and finally;6) a dissertation seminar. A lively course on Ethical Conduct of Science is mandatory. An extremely vigorous and high-quality weekly seminar series in which leaders in the field present their most recent research relevant to the program, supplement the training. Ample time is provided for interaction with the speakers in one-on-one meetings with interested students in an informal lunch setting. Trainees also have a seminar series for presenting their research to CCB students and faculty. A high faculty to student ratio and awareness that training graduate students is important to the faculty strengthens the program. This multidisciplinary research training is carried out within an intellectually integrated and well-equipped collection of member labs, and within a uniquely interactive and communicative research environment. Expansion into the new Mission Bay campus has greatly strengthened the program by providing state of the art chemistry and chemical biology lab space.